202 research outputs found
Agricultural Management and Climatic Change Are the Major Drivers of Biodiversity Change in the UK
Action to reduce anthropogenic impact on the environment and species within it will be most effective when targeted towards activities that have the greatest impact on biodiversity. To do this effectively we need to better understand the relative importance of different activities and how they drive changes in species’ populations. Here, we present a novel, flexible framework that reviews evidence for the relative importance of these drivers of change and uses it to explain recent alterations in species’ populations. We review drivers of change across four hundred species sampled from a broad range of taxonomic groups in the UK. We found that species’ population change (~1970–2012) has been most strongly impacted by intensive management of agricultural land and by climatic change. The impact of the former was primarily deleterious, whereas the impact of climatic change to date has been more mixed. Findings were similar across the three major taxonomic groups assessed (insects, vascular plants and vertebrates). In general, the way a habitat was managed had a greater impact than changes in its extent, which accords with the relatively small changes in the areas occupied by different habitats during our study period, compared to substantial changes in habitat management. Of the drivers classified as conservation measures, low-intensity management of agricultural land and habitat creation had the greatest impact. Our framework could be used to assess the relative importance of drivers at a range of scales to better inform our policy and management decisions. Furthermore, by scoring the quality of evidence, this framework helps us identify research gaps and needs
Updated measurement of decay-time-dependent CP asymmetries in D-0 -> K+ K- and D-0 -> pi(+)pi(-) decays
A search for decay-time-dependent charge-parity (CP) asymmetry in D0 \u2192 K+ K 12 and D0 \u2192 \u3c0+ \u3c0 12 decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13 TeV, and corresponding to an integrated luminosity of 5.4 fb^ 121. The D0 mesons are required to originate from semileptonic decays of b hadrons, such that the charge of the muon identifies the flavor of the neutral D meson at production. The asymmetries in the effective decay widths of D0 and anti-D0 mesons are determined to be A_\u393(K+ K 12) = ( 124.3 \ub1 3.6 \ub1 0.5)
7 10^ 124 and A_\u393(\u3c0+ \u3c0 12) = (2.2 \ub1 7.0 \ub1 0.8)
7 10^ 124 , where the uncertainties are statistical and systematic, respectively. The results are consistent with CP symmetry and, when combined with previous LHCb results, yield A_\u393(K+ K 12) = ( 124.4 \ub1 2.3 \ub1 0.6)
7 10^ 124 and A_\u393(\u3c0+ \u3c0 12) = (2.5 \ub1 4.3 \ub1 0.7)
7 10^ 124
Determination of quantum numbers for several excited charmed mesons observed in B- -> D*(+)pi(-) pi(-) decays
A four-body amplitude analysis of the B − → D * + π − π − decay is performed, where fractions and relative phases of the various resonances contributing to the decay are measured. Several quasi-model-independent analyses are performed aimed at searching for the presence of new states and establishing the quantum numbers of previously observed charmed meson resonances. In particular the resonance parameters and quantum numbers are determined for the D 1 ( 2420 ) , D 1 ( 2430 ) , D 0 ( 2550 ) , D ∗ 1 ( 2600 ) , D 2 ( 2740 ) and D ∗ 3 ( 2750 ) states. The mixing between the D 1 ( 2420 ) and D 1 ( 2430 ) resonances is studied and the mixing parameters are measured. The dataset corresponds to an integrated luminosity of 4.7     fb − 1 , collected in proton-proton collisions at center-of-mass energies of 7, 8 and 13 TeV with the LHCb detector
Updated measurement of decay-time-dependent CP asymmetries in D-0 -> K+ K- and D-0 -> pi(+)pi(-) decays
A search for decay-time-dependent charge-parity (CP) asymmetry in D-0 -> K+ K- and D-0 -> pi(+)pi(-) eff decays is performed at the LHCb experiment using proton-proton collision data recorded at a center-of-mass energy of 13 TeV, and corresponding to an integrated luminosity of 5.4 fb(-1). The D-0 mesons are required to originate from semileptonic decays of b hadrons, such that the charge of the muon identifies the flavor of the neutral D meson at production. The asymmetries in the effective decay widths of D-0 and (D) over bar (0) mesons are determined to be A(Gamma)(K+ K-) = (-4.3 +/- 3.6 +/- 0.5) x 10(-4) and A(Gamma) (K+ K- ) = (2.2 +/- 7.0 +/- 0.8) x 10(-4), where the uncertainties are statistical and systematic, respectively. The results are consistent with CP symmetry and, when combined with previous LHCb results, yield A(Gamma) (K+ K-) = (-4.4 +/- 2.3 +/- 0.6) x 10(-4) and A(Gamma) (pi(+)pi(-))= (2.5 +/- 4.3 +/- 0.7) x 10(-4)
The First Recordings of Calls of the Jerdon\u27s Courser Rhinoptilus Bitorquatus (Blyth), Family Glareolidae
Volume: 101Start Page: 26End Page: 2
Further declines of the Western Capercaillie <i>Tetrao urogallus</i> in Scotland as shown by the 2021–2022 winter survey
The estimated number of Western Capercaillies Tetrao urogallus in Scotland in winter 2021–2022 was 532 with a 95% confidence interval (CI) of 227–810. To produce an updated estimate of the number of Western Capercaillies in Scotland. Line transects were surveyed across the current distribution, sampling in two separate strata: a primary stratum in the core range and a secondary stratum in peripheral areas. Multi-covariate distance sampling was used to fit alternative detection functions to the sighting data, deriving national, regional and sex-specific estimates of abundance. The survey recorded 115 Western Capercaillies in 104 separate encounters across 635 transects, yielding a population estimate of 532 individuals (95% CI: 227–810). This estimate was 52% lower than from the population survey in 2015–2016 (1114 individuals, 95% CI: 805–1505). Declines were greater for females than for males, leading to an adult sex ratio in favour of males. Most of the population (80%) continues to be concentrated in the region of Badenoch and Strathspey. With the population at its lowest level since the start of national monitoring in 1992–1994, the likelihood of extinction in Scotland for a second time seems inevitable without a step-change in conservation action. Measures to improve breeding success and survival are needed and should be targeted in the core of the range to maximize impact on the population.</p
The status of the UK breeding European Turtle Dove <i>Streptopelia turtur</i> population in 2021
The first UK European Turtle Dove Streptopelia turtur survey, in 2021, estimated the breeding population at 2092 territories. Changes in European Turtle Dove abundance in the UK have been monitored through schemes like the BTO/JNCC/RSPB Breeding Bird Survey, however, sample size is now too low to calculate robust trends going forward. The aims of this volunteer-based survey were to provide a new UK population estimate and create a baseline to monitor future population trends. A stratified random sample of one-kilometre squares were surveyed within the core counties for the species. Elsewhere, one-kilometre squares containing recent European Turtle Dove records were targeted. The survey used a two-visit territory mapping approach, with observers asked to get within 200 metres of potentially suitable nesting or foraging habitat. Visits were undertaken in the early morning, to coincide with peak vocal activity, from 11 May to 31 July. The UK population estimate in 2021 was 2092 territories (95% confidence limits, 1559–2782). The species has become increasingly restricted to eastern and southeastern England, with 62.5% of the population estimated to occur in three counties: Kent (682 territories; 32.6%), Suffolk (326; 15.6%) and Essex (300; 14.3%). Additional hotspots occurred in other counties in eastern England, up to North Yorkshire. This result suggests a 98% decline in abundance since the 1968–1972 breeding atlas, similar to trends identified from UK bird monitoring schemes, and a substantial contraction in range since the 2007–2011 bird atlas. The temporary cessation of hunting along their European western flyway provides a vital window of opportunity to scale up the delivery of high-quality breeding habitat and increase food availability in the UK. The survey should be repeated in 2026, and regularly thereafter, to help monitor the effectiveness of conservation interventions.</p
Measurement of the Z 0 line shape parameters and the electroweak couplings of charged leptons
Contains fulltext :
125119.pdf (preprint version ) (Open Access
A test of higher-order electroweak theory in z0 decays to 2 leptons with an associated pair of charged-particles
Contains fulltext :
124397.pdf (publisher's version ) (Open Access
Measurement of three-jet distributions sensitive to the gluon spin ine + e − annihilations at s√=91 GeV
Contains fulltext :
124457.pdf (publisher's version ) (Open Access
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